Epitaxial growth

What is the typical thickness range of the epitaxial layer on silicon epi wafers for LSIs and power devices?

  1. AA few nanometers
  2. BA few micrometers to several tens of micrometers
  3. CA few millimeters
Show answer and explanation

Answer: B. A few micrometers to several tens of micrometers

Epi layers for logic and image sensors are a few micrometers thick, while those for high-voltage power devices can be several tens of micrometers or more. They are very thin compared with the wafer itself, which is about 775 µm thick.

  • A. A few nanometers is the thickness of ultra-thin layers such as quantum wells.
  • B. Correct. A few to several tens of micrometers is typical.
  • C. A few millimeters is thicker than the wafer itself, not an epi layer thickness.
Practice this topic Back to topic

More Epitaxial growth questions

  1. In silicon epitaxial growth, what is the main role of the large flow of hydrogen (H2) supplied along with the source gas?
  2. Which method is used to grow thick GaN layers quickly to make free-standing GaN substrates?
  3. Which is closest to the density of threading dislocations, which run up to the film surface, in GaN grown on sapphire?
  4. In bipolar transistors and similar devices, what is the main purpose of a heavily doped layer (buried layer) beneath the epitaxial layer?
  5. Which is closest to the typical growth temperature for SiC epitaxy (CVD)?